What is sickle cell anemia?

Sickle cell anemia is a blood disease that affects red blood cells. Normal red blood cells are round. In people with sickle cell anemia, hemoglobin – a substance in red blood cells – becomes defective and causes the red blood cells to change shape. The faulty hemoglobin is called hemoglobin S, (HgbS) and it replaces normal hemoglobin called: hemoglobin A (HgbA). Over time, the red blood cells become rigid and shaped like crescent moons or sickles.

The sickle-shaped red blood cells:

  • Clog blood vessels, causing episodes of pain and cutting off oxygen to tissues and organs.
  • Get trapped in the spleen (an organ that gets rid of old cells) where they are destroyed. The body cannot replace the lost cells fast enough. As a result, the body has too few red blood cells, a condition known as anemia.

Sickle cell anemia is a serious disease that can require frequent hospital stays. Children and young adults can die from the disease.

Who gets the disease?

In the United States, the disease occurs most often among African-Americans (in about 1 of every 400 African-American births) and among Hispanics of Caribbean ancestry (1 in every 1,000 to 1,400 Hispanic-American children). Throughout the world, the disease is also found among people of Arabian, Greek, Italian, Sardinian, Turkish, Maltese, and southern Asian ancestry.

Is there a difference between sickle cell anemia and sickle cell trait?

Yes. A person can have a mixture of normal and faulty hemoglobin in their red blood cells without having sickle cell disease. This condition is called "sickle cell trait." People with sickle cell trait have enough normal hemoglobin in their red blood cells to prevent the cells from sickling. One in 12 African-Americans in the United States has sickle cell trait.

It's important to remember that people with sickle cell trait do not have sickle cell disease. They also usually do not develop sickle cell disease, except in unusual circumstances. However, people with sickle cell trait can genetically pass the trait to their children. If two people with sickle cell trait have children together, there is a 1 in 4 chance that their children will have sickle cell anemia.

What are the chances that my child will be born with sickle cell anemia or sickle cell trait?

If you and your partner both have sickle cell trait, your child has a 25% chance of being born with sickle cell anemia. If only one of you has sickle cell trait, your child cannot be born with sickle cell anemia, but there is a 50% chance that your child will be born with sickle cell trait.

If one parent has sickle cell disease and one parent has sickle cell trait, there is a 50% chance that their children will be born with sickle cell disease.

How does a person get sickle cell anemia?

People with sickle cell anemia inherit the disease, which means that the disease is passed on to them by their parents as part of their genetic makeup. Parents cannot give sickle cell anemia to their children unless they both have the faulty hemoglobin in their red blood cells.

What are the symptoms and complications of sickle cell anemia?

  • Periods of pain that can last a few hours to a few days.
  • Blood clots.
  • Swelling in hands and feet.
  • Joint pain that resembles arthritis.
  • Life-threatening infections.
  • Anemia (decrease in red blood cells).

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